Q: i have a new Mac i am trying to transfer my older music from my iPod into my Mac

Do you still have your old computer? If so, then transfer the entire /Home/Music/iTunes/ folder to your new computer. You can do this in several ways:

1. Connect the two using Firewire cable and place the old computer into Target Disk Mode.
2. Copy the folder from the old computer to an external drive then restore it to the new computer.
3. Connect the two via Firewire cable and use Migration Assistant to transfer your entire Home folder.
4. Put both computers on your local network and transfer via File Sharing.
   

Downloading past purchases from the App Store, iBookstore, and iTunes Store

iTunes Store- Transferring purchases from your iOS device or iPod to a computer

Phone to Mac - Pod to Mac

Your i-device was not designed for unique storage of your media. It is not a backup device and media transfer was planned with you maintaining a master copy of your media on a computer which is itself properly backed up against loss.  To use a device with a new computer you transfer the content from the old computer (or its backup) directly to the new computer, not the device to the new computer. Syncing is one way, computer to device, updating the device content to the content on the computer, not updating or restoring content on a computer. The exception is iTunes Store purchases which can be transferred to a computer.

iTunes Store: Transferring purchases from your iOS device or iPod to a computer - http://support.apple.com/kb/HT1848 - only purchases from iTunes Store

For transferring other items from an i-device to a computer you will have to use third party commercial software.  See this document by turingtest2: Recovering your iTunes library from your iPod or iOS device - https://discussions.apple.com/docs/DOC-3991